ignition boxs keep going bad

[foley94jeep]

I have a 94 YJ w/ a 77 304 and, I have 12V at start running to ignition box 14.4V when it is running is that to much I check grounds. Thanks, Kurt Foley

[BillM]

Well I know a GM alternator usually puts out about 14 volts or so all the time. So that may not be bad at all.

[mullins87]

14.4 volts is typical when the engine is running. In fact, if you look at some of your electrical accessories, such as a radio, it will list its operating voltage at 14.4 volts. I would definitely check your ground. Another thing would be to check the gapping on your spark plugs. Too wide of a gap will create higher resistance in the system, leading to increased heat build-up in the ignition box and eventual failure. What about your plug wires? Are they old? Old wires could also have too much resistance in them. Rule of thumb on those is 1k ohms resistance per foot of length. Hence an 18" plug wire should have approximately 1.5k ohms resistance.